Technical Field
The present invention relates to a nanopore structure, an ion device using a nanopore structure, and a method of manufacturing a nano membrane structure, and more particularly, to a nanopore structure body using a nanopore structure formed on an insulating support member, an ion device using a nanopore structure, and a method of manufacturing a nano membrane structure.
Description of the Related Art
A nanopore was started as DNA base sequence analysis technology using α-hemolysin, which is protein of a form structurally having a hole of a nano size. After putting a protein nanopore in an electrolyte containing DNA, when applying a voltage to electrodes of both sides, DNA having negative electric charges passes through a nanopore of 1.5 nm. In this case, when measuring a current drop occurring while DNA blocks a flow of ions, it can be seen that which base sequence has passed through and thus a DNA base sequence may be analyzed. However, in a protein nanopore, a size thereof is structurally fixed to 1.5 nm and the protein nanopore has no good stability and thus the protein nanopore has a fatal drawback that measurement is available only for a short time of less than 1 hour.
In order to overcome such limitations, a solid-state nanopore having free fore size controllability and excellent stability was appeared. A method of stably forming a silicon nitride (SiN) nanopore through a semiconductor process based on silicon (Si) has been developed to be used as an instrument for analyzing various biomolecules or nano particles such as protein, RNA, and virus in addition to DNA base sequence analysis. However, because an ion device using a silicon nitride nanopore formed on a silicon substrate has no good signal to noise ratio, the ion device has a limitation in various use and accurate analysis.
In order to solve a noise problem of such an ion device using a nanopore based on silicon, various attempts have been suggested. A method of reducing an exposure area on an electrolyte of a silicon nitride nanopore membrane, a method of coating or depositing a dielectric material such as silicon oxide (SiO2) or polydimethylsiloxane (PDMS) in an upper portion or a lower portion of a silicon nitride nanopore membrane, and a method of using an insulating support member such as polydimethylsiloxane (PDMS) or glass instead of silicon are representative methods. When using such a method, while adjusting a size of a nanopore and a thickness of a nanopore membrane to a nanometer level, a signal to noise ratio may be remarkably enhanced.
However, in an ion device in which a silicon nitride nanopore membrane is formed on an insulating support member, there is a drawback that it is not easy to transfer the silicon nitride nanopore membrane onto the insulating support member. Particularly, polymethyl methacrylate (PMMA) used as a transfer support layer of a silicon nitride nanopore membrane is not completely removed but remained as a residual material even after transfer of the silicon nitride nanopore membrane to deteriorate accuracy of analysis.